Tập nghiệm của bất phương trình \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaeWaaeaaca % aIYaWaaWbaaSqabeaacaWG4bWaaWbaaWqabeaacaaIYaaaaSGaeyOe % I0IaaGinaaaakiabgkHiTiaaigdaaiaawIcacaGLPaaacaGGUaGaci % iBaiaac6gacaWG4bWaaWbaaSqabeaacaaIYaaaaOGaeyipaWJaaGim % aaaa!43F9! \left( {{2^{{x^2} - 4}} - 1} \right).\ln {x^2} < 0\) là
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Lời giải:
Báo sai\(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaeWaaeaaca % aIYaWaaWbaaSqabeaacaWG4bWaaWbaaWqabeaacaaIYaaaaSGaeyOe % I0IaaGinaaaakiabgkHiTiaaigdaaiaawIcacaGLPaaacaGGUaGaci % iBaiaac6gacaWG4bWaaWbaaSqabeaacaaIYaaaaOGaeyipaWJaaGim % aiabgsDiBpaadeaaeaqabeaadaGabaabaeqabaGaaGOmamaaCaaale % qabaGaamiEamaaCaaameqabaGaaGOmaaaaliabgkHiTiaaisdaaaGc % cqGHsislcaaIXaGaeyOpa4JaaGimaaqaaiGacYgacaGGUbGaamiEam % aaCaaaleqabaGaaGOmaaaakiabgYda8iaaicdaaaGaay5EaaaabaWa % aiqaaqaabeqaaiaaikdadaahaaWcbeqaaiaadIhadaahaaadbeqaai % aaikdaaaWccqGHsislcaaI0aaaaOGaeyOeI0IaaGymaiabgYda8iaa % icdaaeaaciGGSbGaaiOBaiaadIhadaahaaWcbeqaaiaaikdaaaGccq % GH+aGpcaaIWaaaaiaawUhaaaaacaGLBbaacqGHuhY2daWabaabaeqa % baWaaiqaaqaabeqaaiaadIhadaahaaWcbeqaaiaaikdaaaGccqGHsi % slcaaI0aGaeyOpa4JaaGimaaqaaiaaicdacqGH8aapcaWG4bWaaWba % aSqabeaacaaIYaaaaOGaeyipaWJaaGymaaaacaGL7baadaqadaqaai % aadAfacaWGobaacaGLOaGaayzkaaaabaWaaiqaaqaabeqaaiaadIha % daahaaWcbeqaaiaaikdaaaGccqGHsislcaaI0aGaeyipaWJaaGimaa % qaaiaadIhadaahaaWcbeqaaiaaikdaaaGccqGH+aGpcaaIXaaaaiaa % wUhaaaaacaGLBbaacqGHuhY2daGabaabaeqabaGaamiEamaaCaaale % qabaGaaGOmaaaakiabgkHiTiaaisdacqGH8aapcaaIWaaabaGaamiE % amaaCaaaleqabaGaaGOmaaaakiabg6da+iaaigdaaaGaay5Eaaaaaa!8DE6! \left( {{2^{{x^2} - 4}} - 1} \right).\ln {x^2} < 0 \Leftrightarrow \left[ \begin{array}{l} \left\{ \begin{array}{l} {2^{{x^2} - 4}} - 1 > 0\\ \ln {x^2} < 0 \end{array} \right.\\ \left\{ \begin{array}{l} {2^{{x^2} - 4}} - 1 < 0\\ \ln {x^2} > 0 \end{array} \right. \end{array} \right. \Leftrightarrow \left[ \begin{array}{l} \left\{ \begin{array}{l} {x^2} - 4 > 0\\ 0 < {x^2} < 1 \end{array} \right.\left( {VN} \right)\\ \left\{ \begin{array}{l} {x^2} - 4 < 0\\ {x^2} > 1 \end{array} \right. \end{array} \right. \Leftrightarrow \left\{ \begin{array}{l} {x^2} - 4 < 0\\ {x^2} > 1 \end{array} \right.\)
\(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeyi1HS9aai % qaaqaabeqaaiabgkHiTiaaikdacqGH8aapcaWG4bGaeyipaWJaaGOm % aaqaamaadeaaeaqabeaacaWG4bGaeyOpa4JaaGymaaqaaiaadIhacq % GH8aapcqGHsislcaaIXaaaaiaawUfaaaaacaGL7baacqGHuhY2daWa % baabaeqabaGaaGymaiabgYda8iaadIhacqGH8aapcaaIYaaabaGaey % OeI0IaaGOmaiabgYda8iaadIhacqGH8aapcqGHsislcaaIXaaaaiaa % wUfaaaaa!5475! \Leftrightarrow \left\{ \begin{array}{l} - 2 < x < 2\\ \left[ \begin{array}{l} x > 1\\ x < - 1 \end{array} \right. \end{array} \right. \Leftrightarrow \left[ \begin{array}{l} 1 < x < 2\\ - 2 < x < - 1 \end{array} \right.\)
